Obesity accounts for up to 15% of all deaths in the U.S. In 2007-2008, the prevalence of obesity among adults was 33.8%. Obesity threatens to reverse the net benefit of declining smoking rates on the U.S. population. It contributes to untimely mortality and reduces quality of life, both of which are further influenced by the frequent co-occurrence of debilitating co-morbidities including depression and cardiovascular diseases. This translates to tremendous health and economic costs. We propose an innovative exploratory research project focusing on patients with a constellation of three chronic conditions: (1) obesity, (2) hypertension, and (3) depression. A team with complementary capacities has been assembled for an analytical epidemiological study at the Palo Alto Medical Foundation Research Institute (PAMFRI), an AHRQ ACTION network member and a component of the Palo Alto Medical Foundation (PAMF), a large non-profit multi-specialty delivery system. PAMF has implemented the EpicCare Electronic Health Record (EHR) system since 2000. Many research and quality improvement efforts related to these three conditions are ongoing at PAMF, including a study jointly funded by the NIH and the American Heart Association, entitled Evaluation of Lifestyle Interventions to Treat Elevated cardiometabolic risk (E-LITE). Underway at one PAMF clinic, E-LITE is a randomized controlled trial (RCT) of two modified forms of a highly successful lifestyle intervention to treat overweight or obese adults. The specific aims are to: (1) Follow the clinical paths of patients with obesity alone versus with the obesity-hypertension-depression constellation, using EHR data from 2000 to 2010. We will examine the interventions these patients receive, including but not limited to, shared medical appointments for obesity or mental health, bariatric surgery, behavioral interventions, and pharmacologic treatment. We will evaluate the progression of the conditions in the constellation among patients stratified by age, gender, race, and disease states and assess the impact of various interventions. (2) Leverage the prospectively collected data in E-LITE to examine the effectiveness of intensive lifestyle interventions for subsets of E-LITE patients with various combinations of the three priority conditions. We will test if the presence of hypertension and/or depression influences the effectiveness of E-LITE interventions in reducing obesity and cardiometabolic risk. (3) Assess how well the sample of patients and physicians in E-LITE represents the patients and physicians in the study clinic and other clinics in PAMF. We will compare characteristics and clinical trajectories of patient participants in E-LITE with non-participating patients who also have obesity in that clinic or elsewhere in PAMF. We will also compare practice styles of E-LITE physicians with non-E-LITE physicians at PAMF. Results of the study can inform current PAMF and national quality improvement measures and treatment guidelines for managing patients with obesity-hypertension-depression, a common and costly constellation of priority conditions. PUBLIC HEALTH RELEVANCE: Obesity accounts for up to 15% of death in the U.S. Hypertension and depression are also leading causes of disability and often co-occur with obesity. We propose an innovative exploratory research project focusing on patients with a constellation of three chronic conditions: (1) obesity, (2) hypertension, and (3) depression. We will evaluate the progression of these conditions in a constellation in a large medical practice with over 650,000 patients. Results of the study can inform current local and national quality improvement measures and treatment guidelines for managing patients with this common and costly constellation of priority conditions.